Flight characteristics of the F-4 Phantom

[bozon]

who cares if a wing is labeled "delta" or not?
I couldnt care less.
OK, I could... so now following the above thread I care even less then before.

[Zimme83]

I like the F-5 as well, maybe not an uber fighter but a really good looking plane. The sleek lines and the delta wing makes the proportions just right.

[eagl]

Eagl, did the conformals on the E have any affect on handling characteristics other than drag?

The conformal tanks increased pitch authority so we could get a couple more degrees AOA if we wanted it.  High drag up at that high AOA made it of limited usefulness except maybe when forced into in a knife fight with a superior performing fighter, in which case the extra pitch authority could be used to try to get a first-shot advantage.  That could force the other plane to defend instead of pressing its offensive advantage.  That could permit a first shot and a separation attempt in some circumstances.  However, if the shot missed or the other pilot didn't flinch, it would leave the F-15E very slow and vulnerable.

The flight control stability rules also had to be modified slightly from the F-15C/D since the CFTs and nav/targeting pods made the F-15E slightly more prone to spins.  The modifications made the plane a touch less agile in some areas, but you could still fool the stability system to get it to flip-flop around. Again, this was of limited utility due to lower thrust/weight and extra drag compared to other fighters but could sometimes be useful in a last-ditch scenario or if flying against clearly inferior opponent.

Also, the CFTs and other added airframe weight increased pitch momentum and inertia.  So while pitch authority was greater, pitch rate and response was slightly slower sometimes.  Again, there were ways to exploit this and make the plane do some unexpected things, but the tactical usefulness of this is limited.

[eagl]

I like the F-5 as well, maybe not an uber fighter but a really good looking plane. The sleek lines and the delta wing makes the proportions just right.

It's not DELTA its TAPERED!  Get it right!

 

[Vraciu]

These are all triangles Vraciu.

(Image removed from quote.)

Yep.  And the F-4 and F-15 wings are not.   Thank you for making my point--again.

[eagl]

A delta wing is a triangle but not necessarily a right triangle.  The trailing edge can have some sweep and the tips can be clipped.  An ogival delta can even have a curved leading edge which means it isn't even a triangle at all (like the concorde).

Vraciu you're beating a really small drum here.  Once again, where exactly is your claimed half-century of expertise in this area that makes you so certain that the only possible planform that can conceivably be called a delta wing is a right triangle with pointy wingtips?

[Vraciu]

A delta wing is a triangle but not necessarily a right triangle.  The trailing edge can have some sweep and the tips can be clipped.  An ogival delta can even have a curved leading edge which means it isn't even a triangle at all (like the concorde).

Vraciu you're beating a really small drum here.  Once again, where exactly is your claimed half-century of expertise in this area that makes you so certain that the only possible planform that can conceivably be called a delta wing is a right triangle with pointy wingtips?

I love how you all use terms like MODIFIED, CLIPPED, CRANKED, ad nauseum. 

It's either a triangle or its not. 

I have repeatedly stated that deltas have poor drag characteristics.   You have proven my point over and over by restating this very thing as to why these wings are modified.   So they're either deltas or they're not.  If they're modified from something they're no longer that something and all the pretzel twisting on earth doesn't change that. 

By this insane reasoning, any wing is a modified delta.    After all, you are saying a delta (triangle) can have more than three sides.  My jet on the ramp right now must be a modified, tapered, extended, cropped delta.   

So, it's a delta (102, Mirage) or it isn't (F-15, F-4).   

At least the ogival can approximate three sides.    It's basically a triangle.   Not a polygon. 

I'm not getting into a sizing contest with you either.  It's not important.   Words have meaning.  Eager isn't anxious and Eagle wings are not deltas. 

[Skuzzy]

Just as an aside, the drag characteristics, of any given wing shape, has nothing to do with it being a "delta" configuration, or not.  The definition of the "delta" design has never included any statement as to its flight characteristics.

Carry on.

[Skuzzy]

Oh, and all the aviation articles I can find about the F15 suggests it is a modified cropped delta shape with a leading-edge sweepback angle of 45°.  Does that sound about right eagl?

[Zimme83]

Clearly not a triangle so no delta:

[PR3D4TOR]

 

(That's one of my favorite Cold War planes  )

[DaveBB]

Oh, and all the aviation articles I can find about the F15 suggests it is a modified cropped delta shape with a leading-edge sweepback angle of 45°.  Does that sound about right eagl?

I've seen it referred to as "trapezoidal" also.

My mistake, the article was talking about the X-15, not F-15.

[Vraciu]

Just as an aside, the drag characteristics, of any given wing shape, has nothing to do with it being a "delta" configuration, or not.  The definition of the "delta" design has never included any statement as to its flight characteristics.

Carry on.

Not true.  Pure delta wings are notorious for high drag particularly at lower speeds.   This is why they're not used. 

The F-15 has traditionally been referred to as a cropped swept back wing, revisionist history aside. 

[zxrex]

Loved the F4.  Last time I saw one fly was at the Battle Creek, MI airshow a few years ago.  They had a F4 and F22 doing a demo, was pretty cool.  Don't think it was the same year, but the F15E demo was really impressive. He did a 360 around crowd at low alt with burners lit.  That thing was shaking the ground with vapor streaming off the wings all the way around.  I'm sure he was light.  He didn't seem to have much of a slowing down problem.

[Vraciu]

I've seen it referred to as "trapezoidal" also.

My mistake, the article was talking about the X-15, not F-15.

More accurate than saying delta.